Adding only suggestion when span not empty

Author: kper

compiler/rustc_parse/src/parser/diagnostics.rs

@@ -1374,9 +1374,17 @@ impl<'a> Parser<'a> {
         kind: IncDecRecovery,
         (pre_span, post_span): (Span, Span),
     ) -> MultiSugg {
+        let mut patches = Vec::new();
+
+        if !pre_span.is_empty() {
+           patches.push((pre_span, String::new()));
+        }
+
+        patches.push((post_span, format!(" {}= 1", kind.op.chr())));
+
         MultiSugg {
             msg: format!("use `{}= 1` instead", kind.op.chr()),
-            patches: vec![(pre_span, String::new()), (post_span, format!(" {}= 1", kind.op.chr()))],
+            patches,
             applicability: Applicability::MachineApplicable,
         }
     }

src/test/ui/parser/increment-notfixed.stderr

@@ -8,6 +8,8 @@ help: use `+= 1` instead
    |
 LL |     { let tmp = i; i += 1; tmp };
    |     +++++++++++  ~~~~~~~~~~~~~~~
+LL |     i += 1;
+   |       ~~~~
 
 error: Rust has no postfix increment operator
   --> $DIR/increment-notfixed.rs:17:12
@@ -21,6 +23,8 @@ help: use `+= 1` instead
    |
 LL |     while { let tmp = i; i += 1; tmp } < 5 {
    |           +++++++++++  ~~~~~~~~~~~~~~~
+LL |     while i += 1 < 5 {
+   |             ~~~~
 
 error: Rust has no postfix increment operator
   --> $DIR/increment-notfixed.rs:25:8
@@ -32,6 +36,8 @@ help: use `+= 1` instead
    |
 LL |     { let tmp_ = tmp; tmp += 1; tmp_ };
    |     ++++++++++++    ~~~~~~~~~~~~~~~~~~
+LL |     tmp += 1;
+   |         ~~~~
 
 error: Rust has no postfix increment operator
   --> $DIR/increment-notfixed.rs:31:14
@@ -45,6 +51,8 @@ help: use `+= 1` instead
    |
 LL |     while { let tmp_ = tmp; tmp += 1; tmp_ } < 5 {
    |           ++++++++++++    ~~~~~~~~~~~~~~~~~~
+LL |     while tmp += 1 < 5 {
+   |               ~~~~
 
 error: Rust has no postfix increment operator
   --> $DIR/increment-notfixed.rs:39:16
@@ -56,6 +64,8 @@ help: use `+= 1` instead
    |
 LL |     { let tmp = foo.bar.qux; foo.bar.qux += 1; tmp };
    |     +++++++++++            ~~~~~~~~~~~~~~~~~~~~~~~~~
+LL |     foo.bar.qux += 1;
+   |                 ~~~~
 
 error: Rust has no postfix increment operator
   --> $DIR/increment-notfixed.rs:49:10
@@ -67,6 +77,8 @@ help: use `+= 1` instead
    |
 LL |     { let tmp = s.tmp; s.tmp += 1; tmp };
    |     +++++++++++      ~~~~~~~~~~~~~~~~~~~
+LL |     s.tmp += 1;
+   |           ~~~~
 
 error: Rust has no prefix increment operator
   --> $DIR/increment-notfixed.rs:56:5